Although classed as fleet torpedo boats (Flottentorpedoboot) by the Germans, they were comparable to contemporary large destroyers.

Hampered by uncooperative Dutch workers and material shortages, none of the ships were completed before the Allies invaded Normandy (Operation Neptune) in June 1944.

The Germans towed the three ships that were most complete to Germany to be finished, but one was sunk en route by Allied fighter-bombers and no further work was done of the pair that did arrive successfully.

[3] The Type 40-class ships had two sets of license-built Parsons geared steam turbines, each driving a single three-bladed 3.15-meter (10 ft 4 in) propeller,[2] using steam provided by three license-built Yarrow boilers that operated at a pressure of 28 kg/cm2 (2,746 kPa; 398 psi) and a temperature of 380 °C (716 °F).

The turbines were designed to produce a maximum of 49,500 shaft horsepower (36,900 kW) for a speed of 35 knots (65 km/h; 40 mph).

The single-shot SK C/30 fired 0.748-kilogram (1.65 lb) projectiles at a muzzle velocity of 1,000 m/s (3,300 ft/s) at a rate of 30 rounds per minute.

The Kriegsmarine originally estimated that the first six ships would be assigned to the 3rd Destroyer Flotilla which was expected to be formed in early 1943.

The destroyers probably had a lower priority for labor and materials than the large numbers of minesweepers being built in Dutch shipyards, so that the first ships were not laid down until 1942.

The ship was in Bremen in October and was then towed to Elbing, East Prussia, in late December to be finished at the Schichau shipyard.

After the yard was shut down on 22 January 1945 due to power failures, a lack of workers and the advancing Soviet forces which were approaching East Prussia, T65 was towed that day to Danzig and then back to Bremen.

Her convoy was attacked by Bristol Beaufighter fighter-bombers from 455 Squadron RAAF that same day and she was sunk off Den Helder.